Computer Viruses are programs that interfere with the working system of the computer. Well before our computer got a virus it's good to some extent we know the type of computer viruses:
1. Compiler Virus, a virus that has been compiled so that it can be executed directly. This is a virus that first appeared in the computer world, and now experiencing rapid development. The first Virs is very tough to eradicate because it is made with low language, assembler. Indeed, the language is suitable to create a virus but it is hard to use them. The advantages of this virus is capable of doing almost all the manipulation that where this is not always accompanied by another type of virus because it is more limited.
2. BC Bagle virus, this virus is one type of virus that is dangerous and has entered the top ranking of the fastest type of virus affecting our computer. Several hours after the release of this virus, there are already 2 pieces Bagle variant (Bagle BD and BE), which spreads via e-mail, computer networks and P2P applications. This virus spreads via e-mail with a variety of different subjects. According to a study from Panda Software BC Bagle virus is seeping into the e-mail with the subject, among others: Re:, Re: Hello, Re: Hi, Re: Thank you, Re: Thanks. Attachment is also diverse, including:. com,. cpl,. exe,. scr. BC Bagle virus is also able to terminate antivirus programs.
2. Virus Files, is a virus that utilizes a file that can diijalankan / executed directly. Usually the files *. EXE or *. COM. But it can also infect files *. SYS, *. DRV, *. BIN, *. OVL and *. OVY. Type virus can move from one media to any type of storage media and spread on a network.
3. Virus System, or better known as Boot virus. Why this is so because the virus utilizes the files used to create a computer system. Often found in the floppy disk / storage place without us. We will use a computer (restart), then this virus will infect the Master Boot Sector and System Boot Sector if an infected floppy disk in the floppy drive / storage.
4. Boot Sector Virus, a virus that utilizes the relationship between computers and storage area for the spread virus.Apabila on the boot sector there is a program that is able to spread themselves and be able to stay in memory for a computer to work, then the program can be called a virus. Boot sector virus that is two viruses that attack and virus that attacks the floppy disk and partition table.
5. Dropper Virus, a program is modified to install a computer virus that becomes the target of attacks. after installed, the virus will spread but did not participate Dropper spread. Dropper can be a filename like Readme.exe or through Command.com which becomes active when the program runs. One program can Dropper there is some kind of virus.
6. Virus Script / Batch, originally known by the name of this virus as the first batch viruses contained in a batch file that is in DOS.Virus script usually often obtained from the Internet because of the benefits of flexible and can run when we play on the internet, this type of virus usually stay in the HTML file (Hype Text Markup Language) is created by using a script such as Javascript, VBScript, 4 and combination of the scripts that activate Active-X programs from Microsoft Internet Explorer.
7. Macro Virus, the virus that is made by using modular programming facilities in an application program such as Ms Word, Ms Excel, Corel WordPerfect, and so forth. Although this virus contained in a particular application but the danger posed no less berbahanya from other viruses.
8. Polymorphic viruses, we can say smart virus because the virus can change its structure after carrying out the task so difficult to detect by antivirus.
9. Stealth virus, the virus is using clever ways, namely by modifying the file structure to meyembunyikan additional program code in it. This code allows the virus to menyembunyika themselves. All kinds of other viruses also take advantage of this code. The sizes of the files did not change after the virus infects a file.
10. Companion Virus, a virus of this type search for *. EXE file to create a *. COM file and copy to put the virus. The reason, the files *. COM *. EXE file run before.
11. Worm, this is a program that is parasitic because it can duplicate itself. However, the worm does not resemble viruses because they do not infect other computer programs. Therefore, the worm is not classified into the virus. Mainframe computers are the type that is often attacked by worm. Spread on other computers over a network. In the development Worm experience "genetic mutation" that in addition to create a new file, he will try to attach itself to a file, the virus is usually called Hybrid.
13. Trojan horse, disebut juga kuda troya. Trojan menginfeksi komputer melalui file yang kelihatannya tidak berbahaya dan biasanya justru tampaknya melakukan sesuatu yang berguna. Namun akhirnya virus menjadi berbahaya, misalnya melakukan format hardisk.
14. Backdoor Alnica, virus yang juga berbahaya ini merupakan salah satu tipe virus Trojan Horse. Merupakan salah satu virus backdoor yang jika berhasil menginfeksi komputer akan mampu melakukan akses dari jarak jauh dan mengambil segala informasi yang diinginkan oleh si penyerang. Sistem operasi yang diserang oleh virus tersebut antara lain : Windows 200, Windows 95, Windows 98, Windows Me, Windows NT dan Windows XP. Virus ini berukuran sebesar 57.856 byte
15. Trojan di Linux. Para pengguna linux Red Hat diharapkan untuk berhati-hati terhadap PATCH yang dikirm melalui e-mail dengan alamat "security@redhat.com" karena itu sebenarnya bukannya patch security tetapi virus Trojan yang bisa mengacaukan sistem keamanan. E-mail peringatan dari Red Hat biasanya selalu dikirim dari alamat "secalert@redhat.com" dan ditandatangani secara digital. Virus ini juga pernah menyerang sistem keamanan Windows tahun 2003 dengan subyek menawarkan solusi keamanan.